Search PubMed⌕ Search

Biomedical subjects

N Roth

Publications and source records attributed to N Roth.

At least 55 records · Page 3Linked to original sources
PubMed1979

[Localization of rhythmic activity around 4/s].

The results of the studies carried out in four carriers of characteristics are presented under localistic aspects proceeding from the different local distribution of rhythmized activity around 4/s with unipopular and bipolar lead technique. A hypothesis of the origin of the activity is presented which would be in agreement with its distribution characteristics and reactivity.

Brain Mapping↗
PubMed1979

[So-called slow posterior activity in the EEG and the sensori-motor reaction time. Results of re-examinations made after 5 years].

Six persons showing what is called slow posterior activity (4/s rhythm) in the electroencephalogram were reexamined after a period of five years. Sensorimotor reaction times were recorded in addition to the electroencephalogram which was analyzed for the frequency of LPA and for the degree of stability of time dependence. The frequency and distinctness of LPA were found to be stable after five years (r = 0.09 and 0.82, respectively; p less than 0.001), whereas the alpha rhythmus of the subjects had undergone considerable changes (r = 0.34; p greater than 0.05). The extension of reaction times to be observed under the influence of LPA was also seen to remain constant (r = 0.79; p less than 0.05). Accordingly, LPA proved an extremely stable characteristic which did not show any substantial variations in the course of five years.

Adult↗
PubMed1978

Axial length and the Hirschberg test.

Axial lengths of 30 eyes (15 subjects), measured by ultrasonography, ranged from 20.6--26.3 mm. Using a fixed light source, each eye was photographed as monocular fixation was changed over an 8-deg range in 2-deg steps. Hirschberg ratios obtained from the photographs show a low correlation with axial length (0.07), and the mean value, 24 prism diopters per millimeter (S.D. = 7), further supports recent recommendations that the traditional ratio of 12 or 14/1 be replaced by a more correct ratio of 22/1.

Adult↗
PubMed1978

Fear of death in the aging.

Fear of death appears to be universal in the psychopathology of aging, although it is frequently repressed. Judicious pharmacotherapy and insightful psychotherapy are effective in treating the elderly. Two case histories are given in illustration. Despite the difficulties of the problem, it is possible to remove this fear of death-that causes one to waste one's later years-to make of old age a useful and contributory period of life.

Aged↗
PubMed1976

Effects of ethosuximide upon psychomotor responses and electromyographic parameters of healthy individuals.

The purpose of this paper was to investigate the effects of anticonvulsant ethosuximide upon physiological parameters, psychomotor reactions and electromyographic criteria. Ethosuximide increased the reaction times to flashes and the choice reaction time in most subjects, often provoked a greater amount of errors during choice reactions and decreased the average heart frequency. The functional activation during the tasks was diminished. The EEG showed no marked qualitative or quantitative changes. Ethosuximide reduced the maximum conduction velocity of the motor nerve and changed the action potential duration but not the action potential shape. There is no exact parallelism between the increase in reaction time and decrease of nerve conduction velocity. The drug effect upon psychomotor reactions seems to be caused by reduction of vigilance and an inhibitory effect upon the individual's motor responsiveness. Like other anticonvulsants, ethosuximide may alter the electrical properties of all excitable membranes and, by this ubiquitous site of action, exerts the described effects.

Action Potentials↗
PubMed1975

The mental content of puerperal psychoses.

The mental concept of puerperal psychoses is considered as having important determinants in body image disturbances. A case is presented of a woman who had had postpartum psychiatric disorders after the birth of each of her two daughters, and who suffered a relapse in identification with her parturient younger daughter.

Body Image↗
PubMed1975

[Influence of various tasks on activation and self-evaluation in a test with equal psychomotor performance].

In two tests, healthy individuals had to perform one tapping-task each. In the first test they had to knock as quickly as possible (without feedback via the motor performance), while in the second test the motor performance of the first experiment was reproduced precisely by means of feedback allowing them to evaluate the result of their action. In the second experiment, the individuals were significantly less activated, and they felt the second task was easier, requiring less performance. The effect of feedback upon the course of activation, and the role of sensation of activation by the individual in judging his own performance are described.

Adult↗
PubMed1975

[Modulation of the photically evoked potentials in the motor cortex of cats by influences of the somatosensory system and the reticular formation].

The influence of somatosensor stimulation and electric stimulation in the mesencephalic reticular formation upon evoked potentials (EP) of the motor cortex (MC) produced by electric stimulation of the Chiasma opticum and the Corpus geniculatum laterale, respectively, was investigated in unnarcotized, immobilized cats. By preliminary electrical stimulation of the contralateral front limb, intensity-dependent changes of the early positive component of the EP in the MC could be produced. Similar changes were found after passive movement of the limb and following electrical stimulation in the reticular formation of the mesencephalon. The EP in the MC completely disappeared after i.v. administration of 15 mg/kg Nembutal. It is concluded that the impulses reaching the MC after stimulation in the visual system can be modulated in various ways, and thus exhibit a relatively high information content. Possible mechanisms of the modulating influences and their significance are discussed.

Animals↗